Daikin Altherma Heat Pump - can you determine whether/how much it is heating radiators or tank?

HomeOwner40

Hi,

We had a Daikin Altherma 3 M (EDLA06E2V3) Air Source heat pump system installed by Octopus in Spetember. (In case it's interesting, we're in Leeds, and we paid £1500 after the grant, which included removing the gas boiler and replacing 3 radiators).

In general, we are extremely pleased with it. Our house is now warm pretty much all the time, as compared with just a few hours when we had the gas heating turned on previously, and it doesn't cost much more.

One minor issue we're having, however, is that sometimes the heat pump doesn't seem to heat the radiators according to the schedule setup. That is, even when the room thermostat is a couple of degrees below the target temperature, and the hot water in the tank is up to temperature, the radiators still don't get warm at the scheduled time--we're on Octopus Cosy, so we have it set to 18 degrees round the clock and set to 21 degrees for the two three hour blocks of cheap electricity Cosy provides.

Anyway, my question is: is there a way to determine exactly what the Daikin Altherma is doing? That is, can one tell whether it is currently heating water in the tank, providing heat for the radiators, or doing nothing because it thinks it is up to temperature? 

I'd like to be able to get an idea of what the heat pump is doing, so that I can use that information to try to adjust the WD curves, or decide to set the set point to Fixed. I don't know how to adjust those settings at the moment, because I don't know what the device is doing, and why it's not heating when it, apparently, should be.

When the unit is turned on, the app always just reports "Heating to Target", it says this even when it is up to or over temperature. Similarly, when the water in the hot water tank is up to temperature, the app still says "Heating to Target". 

The only methods I have to monitor it is to go outside and see if it's blowing cold air out, or to try to estimate whether it's drawing any electricity by looking at the overall house usage.

Has anyone else experienced a Daikin heat pump not coming on when it seems like it should? How did you fix it?

Very many thanks in advance,

smallblueplanet

Here's a link to a guide to the Daikin MMI that someone on the unofficial FB group has annotated. It might help with what things do? But whether something is CH or DHW is shown under MMI/Information/Actuators.

https://docs.google.com/document/d/1f3cHgvT_GU_OQ27A8WeqMreP0z6w5Nt4BvpB_tHWR9o/edit?fbclid=IwY2xjawGwGVhleHRuA2FlbQIxMAABHQp80s4QN-jYZfIqljdO0jXcSVATlZ3fD0WEUfMSzccLZEQDmqmXxq9N0w_aem_SE3Pe5NkAYEyqvCRCHwFrQ&tab=t.0#heading=h.mrhz5df26ovx

Spies

Turn reheat off on DHW and just set a fixed schedule if you get through more hot water than one tank produces.

smallblueplanet

HomeOwner40 said: ...Anyway, my question is: is there a way to determine exactly what the Daikin Altherma is doing? That is, can one tell whether it is currently heating water in the tank, providing heat for the radiators, or doing nothing because it thinks it is up to temperature? ...

In the MMI there is the Information option, if you then choose Actuators it tells you what is On. If you go back one (return arrow) then choose Sensors it tells you what temperatures things are and right down the bottom it tells you the Flow Rate.